def three():
for x in aoc_utils.input_int_list():
complements = main(2020 - x)
if len(complements) <= 0:
continue
if x + complements[0] + complements[1] == 2020 and not (
complements[0] == x or complements[1] == x):
return x * complements[0] * complements[1]
def main(target):
array = [False] * target
for x in aoc_utils.input_int_list():
if x < target:
array[x] = True
for i in range(target):
if array[i] and array[target - i]:
return i, (target - i)
return []
#!/usr/bin/python3
from collections import *
import itertools
import random
import re
import sys
import aoc_utils
xs = [0] + sorted(aoc_utils.input_int_list())
di = {}
for i, x in enumerate(xs):
di[x] = [x + j for j in [1, 2, 3] if x + j in xs[i + 1 : i + 4]]
e = max(di.keys())
cache = {}
def paths(k):
p = 0
if k >= e:
return 1
for s in di[k]:
if s not in cache:
cache[s] = paths(s)
p += cache[s]
return p
#!/usr/bin/python3
import itertools
import random
import re
import sys
from collections import *
import aoc_utils
def main(xs: list[int]) -> int:
print(sum(x < y for x, y in zip(xs, xs[3:])))
print(sum([1 for i, num in enumerate(xs[3:]) if num > xs[i]]))
count = 0
for i in range(2, len(xs) - 1):
if sum(xs[i - 1:i + 2]) > sum(xs[i - 2:i + 1]):
count += 1
return count
if __name__ == "__main__":
print(main([199, 200, 208, 210, 200, 207, 240, 269, 260, 263]))
print(main(aoc_utils.input_int_list()))
#!/usr/bin/python3
from collections import *
import itertools
import random
import re
import sys
import aoc_utils
"""
My answers were
Part A: 167829540
Part B: 28045630
"""
inp = aoc_utils.input_int_list()
preamble = 25
"""
Finding all the sums of two numbers in the `preamble` length subarray
Create a dictionary, in which keys are the sums of two numbers and the value
is a tuple containing the indices of the two numbers that produced this sum.
Although there are two nested for loops, it turns out as O(preamble * n),
which is essentially O(n).
"""
di = {}
for i in range(preamble, len(inp)):
for j in range(i - preamble, i):
di[inp[i] + inp[j]] = (i, j)